Fluorescent tube fixture and hardware



June 1963 R. w. LESTER 3,0

FLUORESCENT TUBE FIXTURE AND HARDWARE Filed Dec. 18, 1959 2 Sheets-Sheet '1 ull" 401 L /4 .P .4 Li 5 3 L E j ZSIVENTOR.

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I L Arron/My June 18, 1963 R. w. LESTER 87 FLUORESCENT TUBE FIXTURE AND, HARDWARE Filed Dec. 18, 1959 2 Sheets- Sheet 2 Fl 6.5 wn

r QM up? Efii m INVENTOR. Zaberi 2:2 dCesZer ,47- rand/7 United States Patent 3,094,287 FLUORESCENT TUBE FIXTURE AND HARDWARE This invention relates to luminous ceilings and, more particularly, to the electrical fixtures and intercoupling hardware for the installation of a plurality of tubular lights in a plane above a translucent surface to illuminate the surface relatively uniformly thereover.

Modern architecture has induced substantial interest in providing improved lighting for large areas. The luminous ceiling, that is, a translucent false ceiling, has received particular stress in its desired attribute of providing uniform, diffused lighting over the entire area covered by such ceilings.

The luminous ceiling usually comprises a translucent false ceiling over which is positioned a plurality of light sources oriented to evenly illuminate the translucent panel.

Since the fluorescent tube is a distributed light source, it is admirably suited to such applications. The typical installation known to the art comprises a plurality of fluorescent tubes arranged in parallel rows over the translucent ceiling. The number of tubes and the spacing therebetween will vary with the illumination required for the application intended.

To install such fluorescent lighting, a corresponding plurality of fixtures are installed in the area. Each fixture must be then hung in the desired plane and power leads run to each fixture. While such installation may be suitable for illumination purposes, the installation expense is unduly high.

Further, the installations known to the art are not easily changed to accommodate changes, such as a change in the desired intensity of illumination.

It is therefore one object of this invention to provide a fixture for luminous ceiling erection which will simplify and decrease erection costs of luminous ceilings.

'It is another object of the invention to provide a system of fixture installation which is particularly adaptable to luminous ceilings and is further characterized by the fact that it can be, if desired, pre-assembled to a considerable degree in a workshop and subsequently erected in component or modular parts on a job site.

It is a further object of the invention to provide a fixture and system of fixtures for installation in a fashion such that they can be staggered in a geometric relationship to each other over an area in order to eliminate shadow bands occurring at the points where tube ends come together.

Other objects and advantages of the invention will in part be obvious and in part appear hereinafter.

'In accordance with a preferred embodiment of this invention, the fixture, particularly suitable for incorporation into a system of fixtures to form a luminous ceiling, comprises a container enclosing a ballast suitable for firing a pair of hot cathode, fluorescent, hairpin-type tubes. Sockets are mounted astraddle the container to receive the firing pins of said pair of tubes. The fixtures are provided with integral tube supports to cantilever the tubes from the fixture with one of said tubes extending from each end thereof. 'In this manner the fixture supportably engages the tubes when the tubes are inserted in the sockets to eliminate the necessity of supports such as rods, arms, and/or braces extending beyond the fixture.

In the ceiling installation the system contemplates ducts serving as supports for fixtures which may be staggered in relationship to each other, and, furthermore, it conice templates systems of fixtures staggered across a ceiling by replacement of outlet boxes in that ceiling, the said geometric arrangement or staggering of fixtures being such that no emphatic or emphasized shadow band resulting from the juxtaposition of tube ends is observable in the system itself following installation.

The ducts in such system provide a plurality of outlets to which such fixtures may be simply coupled for both initial installation, and for in service changes such as system modification and/ or service replacement.

Referring now to the drawings fora more detailed exposition of the structure of the invention,

FIGURE 1 is a perspective view of a fixture in accordance with this invention.

FIGURE 2 is an exploded view of the fixture shown in FIGURE 1.

FIGURE 3 is a partially exploded perspective view of a typical installation using the fixture shown in FIG- URE 1.

FIGURE 4 is a plan view of a typical ceiling installation using the fixture shown in FIGURE 1.

FIGURE 5 is a plan view of a modified form of ceiling installation using the fixture shown in FIGURE 1.

FIGURE 6 is an exploded view of a ceiling installation with a conventional electrical junction box.

FIGURE 7 is a plan view of a typical ceiling installation using staggered fixtures to eliminate shadow bands an the translucent panels, and

FIGURE 8 is a perspective view of a fixture having sockets for tube interleaving.

In FIGURE 1 there is shown a fixture 14} which comprises ballast container defined by side walls 12 and 13 joined to top Wall 14. Ends 15 and 16 extend outwardly beyond the width of the fixture and carrying openings 19, 20 and 21, 22 respectively, dimensioned to pass the diameter of an appropriate U-shaped tube. Mounted astraddle the container and joined to the side walls thereof are socket housings 23 and 24. Back socket housing assembly encloses two sockets to receive and engage the pins of a hot cathode fluorescent tube. One socket 25 faces one end of the fixture to receive the tube inserted through aperture 26 in the end wall of the socket housing; the other socket is similarly disposed in the opposite direction so that the fixture may carry tubes projecting outwardly from each end of the fixture.

The sockets are preferably mounted so that they float slightly; that is, the sockets may move slightly within the socket housing so that they may align themselves with the pin of the inserted tube.

The socket aperture 26 is aligned with the aperture 20 in the end wall extension, and both apertures are dimensioned to pass the diameter of the inserted tube. When the tube is inserted in the fixture, the aligned apertures supportably engage the tube to cantilever the tube in the desired position. It is often found desirable to insert a grommet 28 such as a polyethylene insert within the aperture. The grommet serves as a cushion for support of the tube and also is deformable to adjust to any slight variation in tube diameter. Substantially, any plastic may be employed for this purpose since the tube temperature is low.

The sockets are wired to the ballast and to the power plug 30 in the top wall of the container. The power plug illustrated is a polarized male plug suitable for plug-in installation of the fixture to a power source.

To illustrate in greater detail the structure of the fixture and a preferred version there-of, FIGURE 2 illustrates a preferred form of fixture in exploded form. Thus, in FIGURE 2 the fixture body as shown consists of essentially a channel 200 which in its preferred version may be extruded so as to give U-shaped female tracks 201, 202, 203 and 204 along its four longitudinal parallel edges.

Internally, longitudinally extending flanges 205 and 206 are provided for mounting of the ballast thereon. Flanges define a longitudinally extending channel between the ballast and the top wall of the container to carry the wiring interconnecting the sockets, and the power plug, and the ballast.

The ballast may thereby be mounted inside the fixture body merely by securing the ballast to the flanges 205 and 206 or by screws or other known conventional mounting means.

The socket housing assembly 23 comprises end wall assemblies 210 and 212, sockets 214, and a housing cover 216. Each end wall assembly is an L-shaped member with the end wall integrally formed with a rectangular lip 218 disposed at perpendicular to the end wall. The mounting wall is slid into position with the edges of the lip fitting until properly positioned on the side of the ballast. The positioning may be maintained by such means as screwing the lip to the side of the ballast by a screw 220. Sockets 214 are mounted on each end wall using interior stand-01f bolts with a small amount of play so that the sockets can float and receive the end pins of the fluorescent tubes.

The housing cover 216 is fundamentally U-shaped having the legs of the U formed with lips 222 at the ends thereof to fit under the channels 201 and 202. The cover may be simply installed by squeezing the legs together and inserting the cover. The springiness of the material will ensure co-operative engagement between the lip and the channel.

The socket is preferably supplied with circumferentially arranged clips which engage a circumferential groove in the pin of the tube. The socket is described in detail in my copending application Serial No. 797,382, filed March 5, 1959 for Fluorescent Tube Fixture.

The end walls and 16 are each provided with flanges 224 and 226. The flanges are spaced apart by the width of the fixture to fit within the channels 201, 202 and 283, 204. The end wall of the fixture can be secured in position by screws 228 securing the flange to the container side wall.

In exploded relationship to the fixture body, there is shown a mounting plate 230 which has its edges turned up to form a small shallow dish. The central section 232 of the mounting plate is shaped and dimensioned to match the service box opening of a wire carrying conduit which commonly is used for carrying a plurality of electric wires. The central section of the mounting plate may be varied in shape to fit the particular service box or opening from which power is to be drawn. Accordingly, the central section 232 is equipped with a female socket 234 which will be connected to wires carried in the conduit or service box to which the plate is .connected.

For carrying the fixture itself the mounting plate is perforated at 236 and 238 in alignment with threaded bolts 240 and 242 which are supportably held by threaded engagement with wing nuts 244 and 246.

In this fashion when the mounting plate has been fastened over a service box, for example by being screwed to the raceway by means of screws passing through openings 248 and 250, it constitutes a firm support for the fixture which is brought to the plate by means of the male plug 30 being inserted into the female plug 234 and the fixture being positively engaged and fastened in place by tightening the wing nuts.

In FIGURE 3 there is shown an assembly such as would be suitable for use in the installation of a ceiling in a building. In such new construction supports 30% and many others like them constitute rods which in a carefully preliminarily planned installation can actually be permanently mounted in the reinforced concrete joists which constitute a rough internal ceiling of the building. At an appropriate level each of these supports has connected thereto a channel bracket 302 fundamentally U- shaped as indicated, the bracket containing extensions for gripping the wire channel or raceway 304. A toggle bolt 306 is passed through the U of the support to provide means for clamping the wireway.

This much of the hardware is merely a typical representation of how a straight line channel of fundamentally conventional form might be supported from the ceiling. Alternatively, channel 304 might be directly attached to the ceiling. As shown channel 304 has its sides formed slightly indented so as to form a projection 308 to be gripped by the hardware described. The channel is completed by a snap-in bottom 310. If the engagement of the bottom is not considered sufficient by means of the snap-in, any positive mounting means may be used, such for example as bolt or screws, depending upon the safety requirements of the particular area in which the installation is being made.

At intervals corresponding to the desired spacing between fixtures, the bottom wall 310 of the channel is provided with openings 312 over which socket plates 232 are screwed after being wired to the wires carried in the channel. In this fashion, the channel serves as an enclosing conduit for carrying the electric service to any portion of the ceiling to be illuminated, and at appropriate intervals along the raceway outlet plates like 230 are connected and wires into the circuit appropriately polarized for receiving the socket 30 for the fixture shown in FIGURE 1. A continuous female socket may be provided in the bottom wall of the channel in the form of a strip socket to allow random spacing of the fixture.

The fixture may then be plugged into the outlet plate and affixed thereto by the wing nuts as set forth in consideration of FIGURE 2. Alternatively, as shown in FIGURE 3, the fixture may be provided with latches 312 which couple the fixture to the plate by cooperation between the keeper 314 on the plate with the latch coupling 316 on the fixture.

The channels will be run over the ceiling in a pattern so that the illumination from the fixtures will be even over the translucent panels suspended below the fixtures. For example, the ceiling layout may be that shown in FIGURE 4.

In FIGURE 4 there is shown a plurality of channels 401 arranged in parallel rows. Spaced along each channel are fixtures 402 carrying hairpin tubes 403 extending outwardly from each end thereof. The spacing between channels, the spacing between fixtures, and the length of the tubes used is determined by the illumination intensity and uniformity desired and the related cost factors of each of the variables.

One of the minor problems which can arise with a fixture structure and system arranged in accordance with the plan in FIGURE 4 is that the back-to-back socket mount called for by the fixtures may, when a plurality of pairs of tubes is illuminated, show a minor shadow line along the line of the raceway. Actually I have found it possible to space the sockets so that the tube ends are only two inches apart. If a reasonable space of approximately 12 to 18 inches is provided between the fixture plane and the diffuser plane, the shadow line will be substantially eliminated.

In the event that the ditfuser plane and the light plane must be close, the lighting layout shown in FIGURE 5 may advantageously be employed.

In FIGURE 5 there is shown a plurality of raceways 5611 carrying fixtures 502 with the hairpin tube 503 extending outwardly from each side thereof. The channels are arranged on closer centers than the arrangement of FIGURE 4, and the fixtures are staggered so as to interleave the tubes from adjacent raceways. By properly choosing the center-to-center distance of the channels with respect to the tube length, substantial decrease in any shadow line eflect may be had.

The embodiment illustrated in FIGURES 3-5 have the desired advantage of substantially decreasing the cost of luminous ceiling installation. The ducts may be prefabricated and prewired. The on-site installation then merely consists of mounting the channels on the ceiling and snapping the fixtures in place on the channels. It will be noted that the channels may be provided with a plurality of outlets arranged closer together than the fixture installation. Thus, it is possible to quickly add new fixtures if the illumination intensity requirement is raised at a future time.

However, the fixture is equally adaptable for use with the conventional outlet boxes such as in a pre-existing ceiling as is shown in FIGURE 6.

In FIGURE 6 there is shown the ceiling junction box 601. The fixture support 602 is provided with a central section 603 having a socket 604 adapted to engage the plug 30 on the fixture 10. The central section is also provided with shaped apertures 605 to receive screws extending from the box 601.

To mount .the fixture support, the socket 604 is wired, the fixture support placed against the box and rotated slightly. The screws may then be tightened to provide a positive, secure mounting. The fixture is then aflixed to the support 602 in manner set forth above.

For bare lighting installations where it is desired to apply some kind of cover, one of metal or otherwise, over the individual fixtures or over the line of fixtures, a cover element 606 may be used. Fundamentally it consists simply of an ornamental sheet metal U wherein the upstanding sides have inwardly extending flanges 607 suitable for engaging the socket housings and thereby forming a cover over the ballast can and socket mouths themselves.

Where it is desired to have a more elaborate cover extending the length of the fixture installation, such as a full line along a raceway, the cover may consist of a U to be supported between fixtures by being suspended from the several cover plates.

When installing a luminous ceiling with outlet boxes, the box location may be arnanged to substantially eliminate any shadow bands, as shown in FIGURE 7.

In FIGURE 7 1 have shown a simplified ceiling installation wherein conventional junction boxes 701 connected by ordinary rigid conduit or flexible cable constitute the power service reaching the outlets. Here the staggering of the outlets can be readily accomplished by so mounting them on the ceiling and passing from one to the next of the zig-zag line indicated by dotted line 702. Actually, a few inches oft from a center line for the staggering of the outlet boxes is sufficient to throw the parts of what would naturally be a shadow line into small spots or shadow in what is otherwise a fully illuminated area, and by the conversion of the shadow line into this scattered spot arangement, virtually the entire shadow line is caused to disappear.

As an alternative version of the fixture wherein the individual fixture minimizes the shadow line, the form of fixture shown in FIGURE 8 may advantageously be employed.

In FIGURE 8 there is shown the fixture 10 comprising container 801 to hold the ballast. The sockets are displaced from axial alignment to allow overlap of the tubes. For example, sockets 802 and 803 for the tube 804 are positioned beyond the center of the container and are displaced to the right of the ballast container center line. Sockets 805 and 806 for tube 807 are displaced to the left. Thus, at the center of the container, the tubes overlap and there is no interruption of light, which might result in a shadow. That is, the ends of the tubes are interleaved to provide a continuous source of illumination.

From the foregoing, the advantages of the fixture should be quite apparent because it will appear that the fixture itself can be made entirely of simple geometric forms, and as shown in FIGURE 3, in forms and dimensions such that the elements are all extrusions or portions of extrusions or simple dye stampings readily assembled into a rugged self-contained unit, need be adapted for the purpose of fabricating luminous ceilings.

This invention may be variously modified and embodied within the scope of the subjoined claims.

What is claimed is:

'1. A lighting fixture for hairpin-type fluorescent tubes which require a ballast for operation thereof which comprise a ballast container having a top and side Walls, each of said side walls having an external, longitudinally extending, female track at each longitudinal edge thereof, each of said side walls having an internal longitudinally extending flange to engage a mounting flange of a ballast for said fixture and which defines a wireway between said flanges and said top wall, a socket mounting flange on each of said side walls, each of said socket mounting flanges comprising a lip slidably engaging said tracks on the side wall and an outwardly extending wall portion having an aperture therethrough, a socket mounted in each of said flanges and aligned with said aperture, a second socket mounting flange on each side wall, and a socket mounted thereon in axial alignment with the sockets on the first flange but oppositely faced, a socket cover housing comprising a U-shaped housing having a lip on the end of each leg thereof, said lip adapted to frictionally engage said tracks in said side Wall.

2. In a ceiling lighting system having a plurality of ducts serving as supports for a plurality of lighting fixtures for hairpin type fluorescent tubes which require a ballast for operation thereof in which each of said fixtures comprises a ballast container, the improvement comprising providing said container with a top and side walls, each of said side walls having an external, longitudinally extending, female track at each longitudinal edge thereof, each of said side walls having an internal longitudinally extending flange to engage a mounting flange of a ballast for said fixture and which defines a wireway between said flanges and said top wall, a socket mounting flange on each of said side walls, each of said socket mounting flanges comprising a lip slidably engaging said tracks on the side wall and an outwardly extending wall portion having an aperture therethrough, a socket mounted in each of said flanges and aligned with said aperture, a second socket mounting flange on each side wall, and a socket mounted thereon in axial alignment with the sockets on the first flange but oppositely faced, a socket cover housing comprising a U-shaped housing having a lip on the end of each leg thereof, said lip adapted to frictionally engage said tracks in said side wall.

References Cited in the file of this patent UNITED STATES PATENTS 1,940,872 Marbury Dec. 26, 1933 2,012,170 Kayatt Aug. 20, 1935 2,227,739 Pollard Jan. 7, 1941 2,301,228 Pollack Nov. 10, 1942 2,494,428 Buck Jan. 10, 1950 2,501,437 Cline Mar. 21, 1950 2,615,123 Guth Oct. 21, 1952 2,616,028 Wiles Oct. 28, 1952 2,667,570 Goldthorpe Jan. 26, 1954 2,907,872 Wilson Oct. 6, 1959 

1. A LIGHTING FIXTURE FOR HAIRPIN-TYPE FLUORESCENT TUBES WHICH REQUIRE A BALLAST FOR OPERATION THEREOF WHICH COMPRISE A BALLAST CONTAINER HAVING A TOP AND SIDE WALLS, EACH OF SAID SIDE WALLS HAVING AN EXTERNAL, LONGITUDINALLY EXTENDING, FEMALE TRACK AT EACH LONGITUDINAL EDGE THEREOF, EACH OF SAID SIDE WALLS HAVING AN INTERNAL LONGITUDINALLY EXTENDING FLANGE TO ENGAGE A MOUNTING FLANGE OF A BALLAST FOR SAID FIXTURE AND WHICH DEFINES A WIREWAY BETWEEN SAID FLANGES AND SAID TOP WALL, A SOCKET MOUNTING FLANGE ON EACH OF SAID SIDE WALLS, EACH OF SAID SOCKET MOUNTING FLANGES COMPRISING A LIP SLIDABLY ENGAGING SAID TRACKS ON THE SIDE WALL AND AN OUTWARDLY EXTENDING WALL PORTION HAVING AN APERTURE THERETHROUGH, A SOCKET MOUNTED IN EACH OF SAID FLANGES AND ALIGNED WITH SAID APERTURE, A SECOND SOCKET MOUNTING FLANGE ON EACH SIDE WALL, AND A SOCKET MOUNTED THEREON IN AXIAL ALIGNMENT WITH THE SOCKETS ON THE FIRST FLANGE BUT OPPOSITELY FACED, A SOCKET COVER HOUSING COMPRISING A U-SHAPED HOUSING HAVING A LIP ON THE END OF EACH LEG THEREOF, SAID LIP ADAPTED TO FRICTIONALLY ENGAGE SAID TRACKS IN SAID SIDE WALL. 